(working title)
Esben Lykke, PhD student
16 marts, 2023
Purpose…
It was likely a dead end from the get-go :(
Basic Features
ACC derived features1
Sensor-Independent Features2
Forger, Jewett, and Kronauer (1999): a so-called cubic van der Pol equation
\[\frac{dx_c}{dt}=\frac{\pi}{12}\begin{cases}\mu(x_c-\frac{4x^3}{3})-x\begin{bmatrix}(\frac{24}{0.99669\tau_x})^2+kB\end{bmatrix}\end{cases}\]
This thing is dependent on ambient light and body temperature!
Walch et al. (2019) incorporated this feature using step counts from the Apple Watch
But as demonstrated by Walch et al. (2019), a simple cosine function does the trick just as well :)
https://github.com/esbenlykke/sleep_study